Stereotactic Radiosurgery for Trigeminal Neuralgia Yields QoL Dividends

Treating trigeminal neuralgia with stereotactic radiosurgery leads to improved outcomes in multiple quality-of-life measures, according to a prospective Cleveland Clinic study recently published online by the International Journal of Radiation Oncology • Biology • Physics.

“For a condition like trigeminal neuralgia that has such a tremendous impact on quality of life, it’s important to determine whether treatment not only lessens pain but improves well-being,” says principal investigator Samuel T. Chao, MD, a radiation oncologist with Cleveland Clinic’s Rosa Ella Burkhardt Brain Tumor and Neuro-Oncology Center. “Our research demonstrates that stereotactic radiosurgery does so for this disease.”

‘The suicide disease’

Stereotactic radiosurgery (using Gamma Knife®) is one of several treatment options for patients with trigeminal neuralgia, a condition that can cause facial pain so severe that the disorder is sometimes called the “suicide disease.” Because the pain typically arises without warning, patients may become shut-ins out of fear of being out in public if an attack occurs.

Medications are not always effective, and those that do work well may be poorly tolerated, especially in older patients, who make up a large share of the affected population.

Hope from radiosurgery — at least on clinical measures

Stereotactic radiosurgery offers a minimally invasive treatment option with rates of pain control of up to 80 percent — especially at doses above 83 Gy — albeit with a risk of resulting facial numbness.

Despite these encouraging pain control rates, data are scarce on radiosurgery’s impact on quality-of-life measures in trigeminal neuralgia. Most studies have had the limitations of being conducted retrospectively, describing physician-reported (rather than patient-reported) outcomes and using categorical pain response scales, which don’t allow quantitative analysis of treatment effects.

Focusing on often-overlooked outcomes

The new study prospectively collected quality-of-life data on 50 patients before and after undergoing stereotactic radiosurgery for trigeminal neuralgia at Cleveland Clinic from 2008 to 2014. Measures were patient-reported using the following questionnaires:

• EuroQol 5-Dimensions (EQ-5D), consisting of ratings of mobility, self-care, completion of usual activities, pain/discomfort, anxiety/depression and self-perceived health status
• Patient Health Questionnaire 9 (PHQ-9), which asks patients to self-report on nine DSM-V criteria for major unipolar depression

All quality-of-life outcomes were collected from patients at routine appointments and entered into a prospectively maintained database at Cleveland Clinic.

According to Dr. Chao and his co-authors, the EQ-5D instrument has not been validated in patients with trigeminal neuralgia but provides multiple advantages for this kind of research. “It’s a global assessment of patient health status that can be applied to different diseases, it is easily completed by patients without physician input, and it provides quantitative quality-of-life measurement, allowing for comparative studies,” explains Cleveland Clinic fellow Rupesh Kotecha, MD, who served as the study’s first author.

Results: Health status improvements accompany pain reductions

Patients’ median age at time of radiosurgery was 65 years (range, 31-85), the median radiation dose was 83 Gy (range, 80-86) and median follow-up was 13 months (range, 3-89). Radiosurgery was the primary treatment for 43 patients (86 percent), with the others having undergone at least one prior surgical procedure.

On the study’s primary clinical outcomes (assessed using Barrow Neurological Institute scales), patients achieved high rates of 12-month freedom from pain failure (92 percent) and 12-month freedom from facial numbness (89 percent).

Meanwhile, patients reported significant benefits in multiple health status measures within approximately five to nine months after stereotactic radiosurgery. Specific results included the following changes from pretreatment status to last follow-up:

• Significant improvements on the EQ-5D (P < .01), driven chiefly by the self-care and pain/discomfort subscores
• Significant improvements in the EQ-5D’s perceived health status score (P = .01)
• Significant improvements in depression as reflected by a reduction in mean PHQ-9 score from 9 to 6 (P = .03)
• A reduction from 50 percent to 18 percent in the proportion of patients reporting extreme problems with pain/discomfort affecting quality of life

On multivariate analysis, higher prescription dose (86 Gy vs. <82 Gy) was the sole variable associated with improvement on the EQ-5D.

Given the small sample size, it was not possible to draw conclusions about selected patient populations, such as those with trigeminal neuralgia that is atypical or multiple sclerosis-related.

A call for QoL evaluations of other therapies

The study authors encourage other institutions to routinely collect and analyze quality-of-life data on their patients. As an example, Dr. Chao cites microvascular decompression as another treatment option for trigeminal neuralgia — one that may offer more permanent pain relief but requires a few days of hospitalization.

“Does microvascular decompression make sense for the elderly?” he asks. “What are the costs compared with improved quality-of-life parameters for various age groups? These kinds of questions are critical for every institution to examine on the treatments they provide.”